A Northern Ireland Ambulance Service (NIAS) paramedic has spoken about the terrifying moment she thought she was going to be killed, after being attacked when responding to a 999 call.

In the video released by the NIAS, paramedic Heather describes the moment she visited an address in Newtownabbey, in December 2012, after receiving a call to say a man was "fitting", only to be physically attacked.

Heather explains how when going upstairs to treat the "patient" they became aggressive and she feared for her life.

She said: "He was a burly 6ft male dressed only in his underpants and was in an agitated state when I arrived.

"I began to try and assess him and he became agressive. I tried to use my radio to report to the control room that the man was quite aggressive.

"He was shouting at me, he was gesturing towards me, we have a defibrillator that we use to carry out assessments and he tried to kick it across the room.

"He fixated his aggression on my radio mic and he tried to pull it off my shirt, which he succeeded in doing, and in doing that he ripped the lapel off my uniform.

"At this point, I couldn't speak to control any longer, I tried to get away from him but the mic was connected to a cable on my belt, as I tried to get away he reeled me in, if you like, using the lead."

Heather said she then attempted to contact control from the emergency button on her radio, but again the reached out to grab it and in doing so, ripped her trousers.

She continued: "At this stage I was trying to get away from him so I went out into the hallway, but he followed me out and grabbed me by the scruff of my shirt and tried to throw me down the stairs."

Heather explained it was at this moment she thought the man was going to kill her, leaving her feeling frightened and isolated.

She added: "He was ripping at my uniform which caused my shirt to become undone, he had already ripped and torn my trousers, he was in a relatively undressed state and I feared for my life, I thought he was going to kill me."

During the incident the man's wife was screaming for him to leave Heather alone, and tried to intervene but the man was physically stronger than both of them.

Heather described how she "wrestled" with the man the entire way down the stairs and miraculously was able to keep her balance.

She said: "I was able to keep my balance the whole way down which I think is what saved me. If I had fallen and if he had of come down on top of me, I would have been killed.

"When we got to the bottom of the stairs, I was able to exit the property, I found myself on the front steps with my shirt ripped off and my trousers ripped and I remembered the gentleman's wife was now in the house on her own.

"So I went back in to make sure she was OK. It's our desire to help people, my conscience wouldn't have let me leave that woman in the house with that gentleman the way he was behaving."

Heather was soon joined by her colleagues at the scene who had heard what was going on in the house when she managed to hit the emergency button on her radio, and suddenly the man changed.

She said: "He completely changed his behaviour at that point, he went from being very aggressive and physical to being a different person.

"My colleague who came through the door first was a big, burly, male paramedic and that made him change his attitude entirely.

"I've never experienced anything like this, it's an element of trust we have when people let us into their homes. This was the first time that anything like this had ever happened me and it unnerved me for a long time.

"He left me very shaken and frightened to go into people's houses."

Heather had to take a period of leave from work following the attack, meanwhile the man who attacked her was never charged or convicted.

She said: "He claimed to have had some sort of blackout and said he couldn't remember what had happened. That disgusts me. There was nothing there to deter him from doing that again to another paramedic.

"Anyone who assaults a paramedic in their line of duty should be death with very seriously by the courts, it needs to be a custodial sentence, nothing less."

Last year NIAS staff were either verbally or physically assaulted on more than 250 occasions.